如何从Android版本棉花糖开始请求从Android拨打电话的许可？

android java runtime-permissions phone-call

2022-09-01 21:34:52

我正在尝试从Android拨打电话，并且我还设置了运行时权限。它询问是否允许打电话。但是当我按允许时，应用程序崩溃了：

这就是我实现它的方式：

private static final int REQUEST_PHONE_CALL = 1;
Intent intent = new Intent(Intent.ACTION_CALL, Uri.parse("tel:" + "+918511812660"));

if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
    if (ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.CALL_PHONE) != PackageManager.PERMISSION_GRANTED) {
        ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.CALL_PHONE},REQUEST_PHONE_CALL);
    }
    else
    {
        startActivity(intent);
    }
}
else
{
    startActivity(intent);
}

@Override
public void onRequestPermissionsResult(int requestCode,
                                       String permissions[], int[] grantResults) {
    switch (requestCode) {
        case REQUEST_PHONE_CALL: {
            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                startActivity(intent);
            }
            else
            {

            }
            return;
        }
    }
}

这是我在logcat中获得的：

java.lang.RuntimeException: Failure delivering result ResultInfo{who=@android:requestPermissions:, 
     request=1, result=-1, data=Intent { act=android.content.pm.action.REQUEST_PERMISSIONS (has extras) }} 
     to activity {com.devpost.airway/com.devpost.airway.activities.MainActivity}: 
     java.lang.NullPointerException: Attempt to invoke virtual method 
     'java.lang.String android.content.Intent.toString()' on a null object reference

      at android.app.ActivityThread.deliverResults(ActivityThread.java:3733)
      at android.app.ActivityThread.handleSendResult(ActivityThread.java:3776)
      at android.app.ActivityThread.-wrap16(ActivityThread.java)
      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1412)
      at android.os.Handler.dispatchMessage(Handler.java:102)
      at android.os.Looper.loop(Looper.java:148)
      at android.app.ActivityThread.main(ActivityThread.java:5461)
      at java.lang.reflect.Method.invoke(Native Method)
      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 
    'java.lang.String android.content.Intent.toString()' on a null object reference
      at android.app.Instrumentation.execStartActivity(Instrumentation.java:1485)
      at android.app.Activity.startActivityForResult(Activity.java:3930)
      at android.support.v4.app.BaseFragmentActivityJB.startActivityForResult(BaseFragmentActivityJB.java:48)
      at android.support.v4.app.FragmentActivity.startActivityForResult(FragmentActivity.java:75)
      at android.app.Activity.startActivityForResult(Activity.java:3890)
      at android.support.v4.app.FragmentActivity.startActivityForResult(FragmentActivity.java:856)
      at android.app.Activity.startActivity(Activity.java:4213)
      at android.app.Activity.startActivity(Activity.java:4181)
      at com.devpost.airway.activities.MainActivity.onRequestPermissionsResult(MainActivity.java:140)
      at android.app.Activity.dispatchRequestPermissionsResult(Activity.java:6582)
      at android.app.Activity.dispatchActivityResult(Activity.java:6460)
      at android.app.ActivityThread.deliverResults(ActivityThread.java:3729)
      at android.app.ActivityThread.handleSendResult(ActivityThread.java:3776) 
      at android.app.ActivityThread.-wrap16(ActivityThread.java) 
      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1412) 
      at android.os.Handler.dispatchMessage(Handler.java:102) 
      at android.os.Looper.loop(Looper.java:148) 
      at android.app.ActivityThread.main(ActivityThread.java:5461) 
      at java.lang.reflect.Method.invoke(Native Method) 
      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726) 
      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

这是什么原因造成的？

答案 1

我最好建议使用ACTION_DIAL而不是ACTION_CALL，同时构造意图来调用特定号码。使用 ACTION_DIAL ，您将不需要应用中的呼叫权限，因为ACTION_DIAL使用已输入的号码打开拨号器，并进一步允许用户决定是否在呼叫之前实际拨打电话或修改电话号码。

Intent intent = new Intent(Intent.ACTION_DIAL, Uri.parse("tel:" + "Your Phone_number"));// Initiates the Intent 
startActivity(intent);

答案 2

堆栈跟踪似乎表明您的权限流工作正常，但对 from 的调用正在崩溃。是否通过以正确设置？我看不到它在代码的那一部分中设置。startActivityonRequestPermissionsResult()IntentstartActivity

另请注意，它代表您处理 SDK 版本检查，因此您应该能够使用ContextCompat.checkSelfPermission

if (ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.CALL_PHONE) != PackageManager.PERMISSION_GRANTED) {
    ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.CALL_PHONE},REQUEST_PHONE_CALL);
}
else
{
    startActivity(intent);
}

本身，没有包装SDK版本检查代码。